sbase/comm.c
FRIGN 0fa5a3e5bb Rename struct linebufline to struct line and add linecmp()
This simplifies the handling in sort(1) and comm(1) quite a bit.
2016-03-10 08:48:09 +00:00

98 lines
1.8 KiB
C

/* See LICENSE file for copyright and license details. */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "text.h"
#include "util.h"
static int show = 0x07;
static void
printline(int pos, struct line *line)
{
int i;
if (!(show & (0x1 << pos)))
return;
for (i = 0; i < pos; i++) {
if (show & (0x1 << i))
putchar('\t');
}
fwrite(line->data, 1, line->len, stdout);
}
static void
usage(void)
{
eprintf("usage: %s [-123] file1 file2\n", argv0);
}
int
main(int argc, char *argv[])
{
FILE *fp[2];
static struct line line[2];
size_t linecap[2] = { 0, 0 };
ssize_t len;
int ret = 0, i, diff = 0, seenline = 0;
ARGBEGIN {
case '1':
case '2':
case '3':
show &= 0x07 ^ (1 << (ARGC() - '1'));
break;
default:
usage();
} ARGEND
if (argc != 2)
usage();
for (i = 0; i < 2; i++) {
if (!strcmp(argv[i], "-")) {
argv[i] = "<stdin>";
fp[i] = stdin;
} else if (!(fp[i] = fopen(argv[i], "r"))) {
eprintf("fopen %s:", argv[i]);
}
}
for (;;) {
for (i = 0; i < 2; i++) {
if (diff && i == (diff < 0))
continue;
if ((len = getline(&(line[i].data), &linecap[i],
fp[i])) > 0) {
line[i].len = len;
seenline = 1;
continue;
}
if (ferror(fp[i]))
eprintf("getline %s:", argv[i]);
if ((diff || seenline) && line[!i].data[0])
printline(!i, &line[!i]);
while ((len = getline(&(line[!i].data), &linecap[!i],
fp[!i])) > 0) {
line[!i].len = len;
printline(!i, &line[!i]);
}
if (ferror(fp[!i]))
eprintf("getline %s:", argv[!i]);
goto end;
}
diff = linecmp(&line[0], &line[1]);
LIMIT(diff, -1, 1);
seenline = 0;
printline((2 - diff) % 3, &line[MAX(0, diff)]);
}
end:
ret |= fshut(fp[0], argv[0]);
ret |= (fp[0] != fp[1]) && fshut(fp[1], argv[1]);
ret |= fshut(stdout, "<stdout>");
return ret;
}